Underground coal mine drilling pulverized coal recycling cross-lane cross-lane filling roadway protection system and process of underground coal mine drilling pulverized coal recycling cross-lane cross-lane filling roadway protection system

Abstract

The invention discloses a coal mine underground drilling pulverized coal recycling cross-lane transverse filling roadway protection system and a process thereof, and belongs to the technical field of coal mine green filling mining, the system comprises a base, a grouting pump, a slurry discharging pool, a double-shaft stirrer, a foaming machine, a spiral feeding machine, a vibrating screen surface device, a water inlet pipeline, a transverse grouting pipeline and a distribution box; the grouting pump is fixed to the base, and an inlet and an outlet are provided with check valves and electric adjusting valves. The double-shaft stirrer is provided with a variable-frequency speed regulation device and a stainless steel paddle; a vibrating screen surface device is a spring steel screen with the frequency of 30-60 Hz; the water inlet pipeline has a backwashing function; a coal-based foam concrete material is adopted in the process, wherein the coal-based foam concrete material comprises 70-80% of Filling is conducted in a layered mode, each layer is 0.5-1 m, the pressure is stabilized for 3-5 minutes under the pressure of 0.5-1 MPa, and filling is completed when the pressure reaches 5 MPa and the material overflows. The system realizes cyclic utilization of slack coal resources, reduces the filling cost, improves the filling compactness and safety, does not influence the later mining coal quality, and is suitable for underground coal filling mining and roof pressure control under complex geological conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mining, in particular to a cross-tunnel and cross-channel filling and protection system for underground coal mine drilling and pulverized coal recovery and utilization and a process thereof. Background Art

[0002] In coal mining operations, the effective treatment of cross-lane rivulets is of great significance for maintaining laneway stability, improving coal recovery rates, and ensuring safe production. However, existing cross-lane rivulet treatment technologies have significant defects. The filling materials used in traditional processes are difficult to achieve the ideal density, which directly leads to problems such as roof subsidence and convergence and deformation of the two sides, seriously threatening the stability of the laneway. Traditional lane protection methods are ineffective, and safety accidents such as roof spalling and roof collapse occur frequently, preventing the working face from advancing normally and greatly increasing the operational risks of front-line workers. In addition, traditional construction methods are inefficient and costly, making it impossible to achieve balanced development of coal mining in terms of economy and safety. Therefore, the development of a new coal mine cross-lane rivulet filling and protection process system with efficient filling capacity, excellent lane protection performance and controllable cost has become a key issue that the industry urgently needs to solve. This has important practical significance for promoting the sustainable development of the coal mining industry. Summary of the Invention

[0003] The purpose of the present invention is to provide a cross-lane and cross-river filling and protection system and process for recycling and utilizing drilled pulverized coal in coal mines, so as to solve the problems of loose filling, poor lane protection effect, low efficiency and high cost in the existing cross-lane and cross-river treatment methods.

[0004] To achieve the above-mentioned object, the present invention provides a tunnel protection system for underground coal mining using cross-tunnel horizontal filling and slicing during drilling of pulverized coal, comprising:

[0005] A base, which provides a supporting foundation for the system and reduces equipment vibration;

[0006] A grouting pump, the grouting pump is fixedly installed on the upper surface of the base, and the inlet and outlet of the grouting pump are both installed with a check valve and an electric regulating valve;

[0007] The slurry discharge pool is symmetrically opened on both sides of the grouting pump. The slurry discharge pool is a concrete structure with an anti-corrosion coating on the inner wall, and is used for temporarily storing processed materials;

[0008] A double-shaft agitator is symmetrically arranged on both sides of the grouting pump and connected to the grouting pump through a high-pressure rubber tube. The double-shaft agitator is composed of a coal mine mixer, with a carbon steel base welded to the bottom of the barrel and a built-in frequency conversion speed regulation stirring device;

[0009] A foaming machine, symmetrically arranged on the side of the biaxial agitator away from the grouting pump, the foaming machine is composed of a mining foaming device, the storage tank is made of PE material, and is equipped with a high-precision metering pump;

[0010] A screw feeder is symmetrically arranged and connected to the double-shaft agitator, used to convey the pulverized coal in the silo to the double-shaft agitator, and has a timed reversal and anti-blocking function;

[0011] A vibrating screen device, wherein the vibrating screen device is a spring steel screen with a mesh size of 3-8 mm, and the vibrating screen device is fixed above the biaxial agitator via a rubber shock-absorbing pad, and has a vibration frequency of 30-60 Hz;

[0012] A water inlet pipeline, which is connected to the grouting pump through a high-pressure resistant rubber tube and is provided with a backwash pipeline and a two-way control valve;

[0013] Yokogawa grouting pipeline, which adopts seamless steel pipe and is used to transport materials in the grouting pump to Yokogawa;

[0014] A distribution box is used for system power supply and equipment control.

[0015] Preferably, the Yokogawa grouting pipeline needs to be hung straight along the top of the Yokogawa, and the slurry delivery line is set from low to high. When the pump stops unexpectedly, the lower pipeline can be opened to allow the slurry to flow back.

[0016] Preferably, the biaxial agitator is a horizontal biaxial agitator, and the agitating blades are 316 stainless steel pitched-blade turbine blades that are polished, and the agitating space covers more than 95% of the volume of the cavity.

[0017] Preferably, the foaming machine is connected to the double-shaft agitator through a PPR pipe, which can accurately adjust the foaming agent delivery rate and mix it with coal powder to form a filling slurry, causing the filling material to foam after filling and increase its volume by 2 to 3 times, thereby achieving effective saving of filling materials.

[0018] A coal mine underground drilling pulverized coal recovery and cross-tunnel horizontal filling and protection tunnel process comprises the following steps:

[0019] S1. When there is coal or gangue in the riverbed, fill it in layers directly with it as the base, and control the thickness of each layer to be 0.5-1 meter;

[0020] S2. Maintain pressure for 3-5 minutes after grouting each layer, maintaining the pressure at 0.5-1MPa;

[0021] S3. When the grouting pump pressure rises to 5 MPa and the grouting material overflows, filling is completed;

[0022] S4. Carry out grouting reinforcement on the lower coal and gangue piles.

[0023] Preferably, coal-based foamed concrete is used as the filling material in S1, with coal powder with particles smaller than 3 mm as the main component, accounting for 70-80%, supplemented by 20% inorganic binder, a water-cement ratio of 0.5:1, and a setting time of 50 minutes.

[0024] Preferably, if the machine is stopped for more than 30 minutes during the filling operation, the filling slurry in the pipeline is released; if the machine is stopped for more than 1 hour, the pipeline and equipment are cleaned in the forward and reverse directions.

[0025] Preferably, when the system detects that the grouting pump or pipeline is blocked, the pipeline is reversely flushed with 0.3-0.8MPa high-pressure water flow through the backwash pipeline of the water inlet pipeline.

[0026] Therefore, the present invention adopts the above-mentioned coal mine underground drilling pulverized coal recovery and utilization cross-lane horizontal river filling and protection system and process, which has the following technical effects:

[0027] (1) The layered compaction process of the filling system of the present invention makes the filling body uniform and stable, can effectively strengthen the tunnel support, and significantly reduce safety risks;

[0028] (2) The present invention directly utilizes coal dust generated at the coal mine excavation site or by drilling as filling material, thereby realizing the recycling of resources, saving a large amount of material costs, and reducing the negative impact of coal mining on the surrounding environment;

[0029] (3) The coal-based foam concrete filling material used in the present invention has the characteristics of light weight and low material consumption. The cement binder material consumed per cubic meter of material is significantly reduced, and the impact on coal quality is greatly reduced, which not only reduces the cost but also improves the applicability of the material.

[0030] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the overall structure of a cross-tunnel horizontal filling and protection system for underground coal mining drilling and pulverized coal recovery and utilization according to the present invention;

[0032] Figure 2 The present invention is a schematic diagram of the principle of a cross-tunnel horizontal filling and protection system for underground coal mine drilling and pulverized coal recovery.

[0033] Reference numerals

[0034] 1. Grouting pump; 2. Slurry discharge tank; 3. Base; 4. Double-shaft agitator; 5. Distribution box; 6. Foaming machine; 7. Screw feeder; 8. Vibrating screen device; 9. Water inlet pipe; 10. Backwash pipe; 11. Yokogawa grouting pipe; 12. Yokogawa. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0036] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0037] like Figures 1 to 2 As shown, a cross-tunnel horizontal filling and protection system for underground drilling and pulverized coal recovery in coal mines includes a base 3. The base 3 is installed on the flat tunnel floor and fixed with anchor bolts to provide a stable support foundation for the entire system and reduce vibration and displacement during equipment operation.

[0038] Fix the ZBQ-750 / 8 hydraulic grouting pump 1 at the center of the upper surface of the base 3, connect the inlet and outlet to high-pressure resistant rubber tubes respectively, and install check valves and electric regulating valves at the inlet and outlet to prevent the slurry from flowing back.

[0039] Two concrete slurry pools 2 are symmetrically poured on both sides of the grouting pump 1. The inner walls of the pools are painted with anti-corrosion coating and plastered to ensure that there is no leakage and corrosion resistance when temporarily storing materials.

[0040] A twin-shaft agitator (4), comprised of two ZJ-1500 coal mine mixers, is symmetrically mounted on either side of a grouting pump (1). A carbon steel base (3) is welded to the bottom of the agitator to enhance stability and moisture resistance. The agitator is connected to the grouting pump (1) via high-pressure rubber tubing. The agitator features polished 316 stainless steel pitched-blade turbine impellers, ensuring the mixing space covers over 95% of the agitator cavity volume. The agitator is equipped with a variable frequency speed control (VVV) for a continuously variable speed adjustment between 80 and 250 rpm.

[0041] Two KPC-12 / 300 mining foaming devices are symmetrically installed on the side of the twin-shaft agitator 4 away from the grouting pump 1. The storage tank is made of PE material and is connected to the stirring unit of the twin-shaft agitator 4 through a PPR pipe. It is equipped with a high-precision metering pump to accurately adjust the foaming agent delivery rate, which is mixed with coal powder to form a filling slurry. This promotes the filling material to foam after filling and increases its volume by 2 to 3 times, which can effectively save filling materials.

[0042] The screw feeder 7 is symmetrically arranged above the feed port of the dual-shaft stirrer 4, with the feed end connected to the silo and the discharge end aligned with the feed port of the dual-shaft stirrer 4 to ensure smooth coal powder transportation, and a timed reversal function is set to prevent blockage.

[0043] A vibrating screen surface device 8 consisting of two spring steel screens with 3-8 mm mesh size is fixed above the dual-shaft stirrer 4 through a rubber shock-absorbing pad. The motor drives the vibrator and the vibration frequency is adjusted to 30-60 Hz. The screening efficiency exceeds 90%.

[0044] The water inlet pipe 9 is connected to the grouting pump 1 through a high-pressure resistant rubber tube, and a backwash pipe 10 and a two-way control valve are set; the Yokogawa grouting pipe 11 adopts a seamless steel pipe, extending from the grouting pump 1 to Yokogawa 12. The Yokogawa grouting pipe 11 is hung straight along the top of Yokogawa 12, and the slurry delivery line is arranged from low to high to ensure that there is no bend.

[0045] The distribution box 5 is installed at a position on the side of the base 3 that is easy to operate, and is connected to the electrical circuits of various devices to realize power supply and control functions.

[0046] A tunnel-crossing and tunnel-protecting technology for underground coal mine drilling and pulverized coal recovery and utilization includes:

[0047] S1. When there is coal and gangue in Yokogawa 12, it is directly layered and filled with the base, with the thickness of each layer controlled at 0.5-1 meter;

[0048] S2. Maintain pressure for 3-5 minutes after grouting each layer, maintaining the pressure at 0.5-1MPa to ensure the filling layer is dense;

[0049] S3. When the pressure of the grouting pump 1 rises to 5 MPa and the grouting material overflows, the filling is completed;

[0050] S4. Carry out grouting reinforcement on the lower coal and gangue piles.

[0051] The filling material in step S1 is coal-based foamed concrete. The specific mix ratio is: 80% coal pulverized coal with particles smaller than 3mm, sourced directly from the underground mining site; 20% inorganic binder; and a strictly controlled water-cement ratio of 0.5:1. The foamed concrete is lightweight and requires minimal material, significantly reducing cement binder consumption per cubic meter. Furthermore, the high proportion of coal pulverized coal in the mix significantly minimizes the impact of coal-based foamed concrete on coal quality.

[0052] The preparation process is as follows: the screw feeder 7 transports the coal powder in the silo to the double-shaft mixer 4, and the large particles of impurities are screened and removed by the vibrating screen device 8; the foaming machine 6 injects the foaming agent into the double-shaft mixer 4 in proportion, mixes and stirs it with the coal powder and water, and the stirring speed is set to 150rpm and the stirring time is 5 minutes to form a uniform filling slurry. The solidification time is about 50 minutes.

[0053] Backwashing and shutdown processing: When the system detects that the grouting pump 1 or the Yokogawa grouting pipeline 11 is blocked, the two-way control valve of the water inlet pipeline 9 is switched to the backwash mode, and the pipeline is reversely flushed with high-pressure water from the water tank. The flushing pressure is maintained at 0.5MPa until the pipeline is unobstructed; if the shutdown time exceeds 30 minutes, open the valve at the end of the pipeline to release the remaining slurry in the pipeline; if the shutdown time exceeds 1 hour, the pipeline and equipment are cleaned forward and reverse.

[0054] The above-mentioned underground coal mine drilling pulverized coal recovery and utilization cross-tunnel cross-channel filling and protection system and process, by using drilled fine coal and coal-based foam concrete materials to fill the cross-channels across the mining area, realizes effective control of roof pressure, and prevents accidents such as frame crushing, roof collapse, and slab spalling when the coal mining machine and hydraulic support pass through the area. This technology and system not only realizes the recovery and reuse of underground drilling fine coal, but also realizes the control of coal mining roof pressure. The filling material has little impact on the coal quality, ensuring the safe, low-carbon and green mining of coal resources.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A cross-tunnel horizontal filling and protection system for underground coal mining drilling and pulverized coal recovery, characterized in that: include: A base, which provides a supporting foundation for the system and reduces equipment vibration; A grouting pump, the grouting pump is fixedly installed on the upper surface of the base, and the inlet and outlet of the grouting pump are both installed with a check valve and an electric regulating valve; The slurry discharge pool is symmetrically opened on both sides of the grouting pump. The slurry discharge pool is a concrete structure with an anti-corrosion coating on the inner wall, and is used for temporarily storing processed materials; A double-shaft agitator is symmetrically arranged on both sides of the grouting pump and connected to the grouting pump through a high-pressure rubber tube. The double-shaft agitator is composed of a coal mine mixer, with a carbon steel base welded to the bottom of the barrel and a built-in frequency conversion speed regulation stirring device; A foaming machine, symmetrically arranged on the side of the biaxial agitator away from the grouting pump, the foaming machine is composed of a mining foaming device, the storage tank is made of PE material, and is equipped with a high-precision metering pump; A screw feeder is symmetrically arranged and connected to the double-shaft agitator, used to convey the pulverized coal in the silo to the double-shaft agitator, and has a timed reversal and anti-blocking function; A vibrating screen device, wherein the vibrating screen device is a spring steel screen with a mesh size of 3-8 mm, and the vibrating screen device is fixed above the biaxial agitator via a rubber shock-absorbing pad, and has a vibration frequency of 30-60 Hz; A water inlet pipeline, which is connected to the grouting pump through a high-pressure resistant rubber tube and is provided with a backwash pipeline and a two-way control valve; Yokogawa grouting pipeline, which adopts seamless steel pipe and is used to transport materials in the grouting pump to Yokogawa; A distribution box is used for system power supply and equipment control.

2. The underground coal mine drilling pulverized coal recovery and cross-tunnel filling and protection system according to claim 1 is characterized by: The Yokogawa grouting pipeline needs to be hung straight along the top of the Yokogawa, and the slurry delivery line is set from low to high. When the pump stops unexpectedly, the lower pipeline can be opened to allow the slurry to flow back.

3. The underground coal mine drilling pulverized coal recovery and cross-tunnel filling and protection system according to claim 1 is characterized by: The double-shaft agitator is a horizontal double-shaft agitator, and the agitating blades are 316 stainless steel inclined-blade turbine blades that have been polished, and the agitating space covers more than 95% of the volume of the cavity.

4. The underground coal mine drilling pulverized coal recovery and cross-tunnel filling and protection system according to claim 1 is characterized by: The foaming machine is connected to the double-shaft stirrer through a PPR pipe, which can accurately adjust the foaming agent delivery rate and mix it with coal powder to form a filling slurry, which promotes the filling material to foam after filling and increase its volume by 2 to 3 times, thereby achieving effective saving of filling materials.

5. A filling process for a cross-tunnel horizontal filling and protection tunnel system for underground coal mining drilling and pulverized coal recovery according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. When there is coal or gangue in the riverbed, fill it in layers directly with it as the base, and control the thickness of each layer to be 0.5-1 meter; S2. Maintain pressure for 3-5 minutes after grouting each layer, maintaining the pressure at 0.5-1MPa; S3. When the grouting pump pressure rises to 5 MPa and the grouting material overflows, filling is completed; S4. Carry out grouting reinforcement on the lower coal and gangue piles.

6. The underground coal mine drilling pulverized coal recovery and cross-tunnel horizontal filling and tunnel protection process according to claim 5 is characterized by: In S1, coal-based foamed concrete is used as the filling material, mainly composed of coal powder with particles less than 3 mm, accounting for 70-80%, supplemented by 20% inorganic binder, with a water-cement ratio of 0.5:1 and a setting time of 50 minutes.

7. The underground coal mine drilling pulverized coal recovery and cross-tunnel horizontal filling and tunnel protection process according to claim 5 is characterized by: If the machine is stopped for more than 30 minutes during the filling operation, the filling slurry in the pipeline should be released; if the machine is stopped for more than 1 hour, the pipeline and equipment should be cleaned in the forward and reverse directions.

8. The underground coal mine drilling pulverized coal recovery and cross-tunnel horizontal filling and tunnel protection process according to claim 5 is characterized by: When the system detects that the grouting pump or pipeline is blocked, it will reversely flush the pipeline with 0.3-0.8MPa high-pressure water flow through the backwash pipeline of the water inlet pipeline.

Images